title: Investigational factor Xa inhibitors for thrombosis and acute coronary syndromes.
abstract: BACKGROUND
  A number of new oral anticoagulant drugs that selectively and directly inhibit factor Xa (FXa) appear as promising alternatives to the existing anticoagulant agents. These compounds present a convenient route of administration with predictable pharmacokinetics and pharmacodynamics that allow fixed dosing regimens without requiring coagulation monitoring. Rivaroxaban is the first of this new class of drugs that was approved for the prevention of venous thromboembolism (VTE) after elective total hip replacement or total knee replacement surgery in the EU, Canada and several other countries. Clinical trials with rivaroxaban in patients with acute VTE and in patients with atrial fibrillation have been recently completed. Numerous other compounds are under different developing stages (apixaban, edoxaban, otamixaban, LY517717, PRT-054021, YM150).
  
  
  METHODS
  This review provides an overview of the two oral anti-FXa drugs at the most advanced stage of development (rivaroxaban and apixaban) and briefly describes and comments on the results of the most important studies.
  
  
  CONCLUSIONS
  Undoubtedly, these new drugs will offer several advantages over the previous compounds, but a number of issues still require some attention during the phase of translation from clinical trials into daily clinical practice.
authors.affiliation: University of Insubria, Research Center on Thromboembolic Disorders and on Antithrombotic Therapies, Department of Clinical Medicine, Varese, Italy.
authors.forename: Erica
authors.initials: E
authors.lastname: Romualdi
authors.forename: Walter
authors.initials: W
authors.lastname: Ageno
mesh_terms: D054058:Acute Coronary Syndrome / Q000188:drug therapy*; D000925:Anticoagulants / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy; D017326:Clinical Trials, Phase III as Topic; D015507:Drugs, Investigational / Q000627:therapeutic use*; D065427:Factor Xa Inhibitors; D006801:Humans; D009025:Morpholines / Q000627:therapeutic use*; D011720:Pyrazoles / Q000627:therapeutic use*; D011728:Pyridones / Q000627:therapeutic use*; D000069552:Rivaroxaban; D020521:Stroke / Q000517:prevention & control; D013876:Thiophenes / Q000627:therapeutic use*; D013927:Thrombosis / Q000188:drug therapy*; D054556:Venous Thromboembolism / Q000188:drug therapy* / Q000517:prevention & control
chemical_list: D000925:Anticoagulants; D015507:Drugs, Investigational; D065427:Factor Xa Inhibitors; D009025:Morpholines; D011720:Pyrazoles; D011728:Pyridones; D013876:Thiophenes; C522181:apixaban; D000069552:Rivaroxaban